Then create an Upstart service startup script for the stream in /etc/init/ezstream-PROJECT.conf:

description "ezstream service for YOUR PROJECT"
author "YOUR NAME"
# Start the service on runlevel 2/3/4/5
start on runlevel [2345]
# Stop the service on runlevel 0/1/6
stop on runlevel [016]
script
# Loop and wait for icecast2 to open port 8000. Change if you are using a different port.
until nc -z localhost 8000; do
echo "Waiting for icecast2 to start"
sleep 1
done
# Start the ezstream instance with a unique name so multiple instances can be run.
exec start-stop-daemon --start --name UNIQUE_SERVICE_NAME --exec /usr/bin/ezstream -- -c /PATH/TO/EZSTREAM/CONFIG.cfg
end script